Updated pediatric liver size ranges from ultrasound

What the study found: The study established updated ultrasound-based reference ranges for pediatric liver size using age and height. It found that liver size increased with age and showed a more linear increase with height.

Why the authors say this matters: The authors say updated, methodologically rigorous reference ranges are needed for pediatric liver size on ultrasound because prior literature had limitations and the pediatric population has changed demographically. The study suggests these new ranges and nomograms may better support assessment of normal liver size.

What the researchers tested: The researchers reviewed abdominal ultrasound reports from January 2014 to December 2024 for patients under 18 years old. They included examinations read as normal and excluded patients with liver disease or abnormal AST and ALT results. They used Generalized Additive Models for Location, Scale, and Shape (GAMLSS) with the Box-Cox Power Exponential distribution to create reference ranges based on age and, in a subset, height.

What worked and what didn't: A total of 4,611 ultrasound examinations met the inclusion criteria, including 2,055 males and 2,556 females. Liver size ranged from 4.9 to 5.5 cm at birth and increased to a maximum of 17.2 cm in adolescents aged 17-18 years; in the 3,235 examinations with height recorded, the model showed a more linear increase with height, with reference ranges reported up to 180 cm and a maximum liver size of 17.5 cm. The conclusion states that normal liver size may be slightly higher than previously reported.

What to keep in mind: This is a retrospective study from a single institution’s ultrasound reports, and the abstract does not describe additional limitations. The reference ranges are based on the study’s included population and measurement approach, which was the craniocaudal dimension of the right lobe along the midclavicular line.

Key points

• The study created updated pediatric liver size reference ranges from ultrasound data.
• Liver size increased with age and more linearly with height.
• The dataset included 4,611 abdominal ultrasound examinations from patients under 18 years old.
• At birth, liver size ranged from 4.9 to 5.5 cm and reached 17.2 cm in adolescents aged 17-18 years.
• The authors conclude normal liver size may be slightly higher than previously reported.